A plurality of electronic components are placed on a circuit board, and for mounting the electronic components, a plurality of terminal parts are provided. Further, a large number of electronic components are required to transmit and receive a large amount of data, resulting in requiring a large number of terminal parts. Still further, along with bezel-slimming in a display panel, development of an organic electroluminescent (EL) panel, and the like, the circuit board used in the display panel is becoming more flexible. Patent Literature 1 described below aims to provide a flexible board having a structure that is not easily disconnected even when bending stress is applied thereto, and the flexible board as recited in Patent Literature 1 described below is characterized in that an insulating film is covered up to a region near a boarder portion between a plurality of electronic component mounting parts (terminal parts) formed on a base substrate having flexibility and a plurality of connection wiring parts continuously provided from the plurality of electronic component mounting parts, and an edge part of the insulating film on a side of the boarder portion is formed in a non-linear shape.